---
id: CVE-2026-103547
title: >-
  In ldapd in OpenBSD 7.8 before errata 057 and 7.9 before errata 021, delegated
  BSD authentication results are correlated only by the LDAP child process
  client file descriptor and LDAP message ID
summary: >-
  In ldapd in OpenBSD 7.8 before errata 057 and 7.9 before errata 021, delegated
  BSD authentication results are correlated only by the LDAP child process
  client file descriptor and LDAP message ID. After a connection closes, a later
  connec…
severity: critical
cvss: 9.2
cvssVector: 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N'
cwe:
  - CWE-863
vendor: OpenBSD
product: OpenBSD
affected:
  - OpenBSD >= 7.8 < errata 057
  - OpenBSD >= 7.9 < errata 021
published: '2026-09-30'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T20:17:31.607'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-103547'
references:
  - url: 'https://ftp.openbsd.org/pub/OpenBSD/patches/7.9/common/021_ldapd.patch.sig'
    label: cve@mitre.org
  - url: >-
      https://github.com/openbsd/src/commit/4f3f58e83c2a6d239c544236a9d4d76c74bbf960
    label: cve@mitre.org
  - url: 'https://www.openbsd.org/errata78.html'
    label: cve@mitre.org
  - url: 'https://www.openbsd.org/errata79.html'
    label: cve@mitre.org
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-30T19:55:41.738525Z'
cvssSource: cna
ingestedAt: '2026-09-30T20:23:19.515Z'
---

## Overview

In ldapd in OpenBSD 7.8 before errata 057 and 7.9 before errata 021, delegated BSD authentication results are correlated only by the LDAP child process client file descriptor and LDAP message ID. After a connection closes, a later connection that reuses the same file descriptor and message ID can receive the earlier authentication result. A remote attacker who can reach ldapd can complete a Bind as another identity. A missing connection can also cause a NULL pointer dereference. (ldapd is not enabled by default.)

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.